bugfix: Fix stream handling in cutedsl gemm (#1509)

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Author: fzyzcjy

flashinfer/cute_dsl/blockscaled_gemm.py

@@ -2710,7 +2710,7 @@ def dtype(cutlass_dtype):
             else None
         )
         # todo(Yingyi): might add cute.assume() for shape alignment?
-        current_stream = cutlass_torch.default_stream()
+        current_stream = cutlass_torch.current_stream()
 
         self.run_cute_ptr(
             a_ptr,